1 /* 2 * Simulate an I2C port 3 * 4 * Copyright (c) 2014 Google, Inc 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <dm.h> 11 #include <errno.h> 12 #include <fdtdec.h> 13 #include <i2c.h> 14 #include <asm/test.h> 15 #include <dm/lists.h> 16 #include <dm/device-internal.h> 17 #include <dm/root.h> 18 19 DECLARE_GLOBAL_DATA_PTR; 20 21 struct dm_sandbox_i2c_emul_priv { 22 struct udevice *emul; 23 }; 24 25 static int get_emul(struct udevice *dev, struct udevice **devp, 26 struct dm_i2c_ops **opsp) 27 { 28 struct dm_i2c_chip *priv; 29 int ret; 30 31 *devp = NULL; 32 *opsp = NULL; 33 priv = dev_get_parentdata(dev); 34 if (!priv->emul) { 35 ret = dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, 36 false); 37 if (ret) 38 return ret; 39 40 ret = device_get_child(dev, 0, &priv->emul); 41 if (ret) 42 return ret; 43 } 44 *devp = priv->emul; 45 *opsp = i2c_get_ops(priv->emul); 46 47 return 0; 48 } 49 50 static int sandbox_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, 51 int nmsgs) 52 { 53 struct dm_i2c_bus *i2c = bus->uclass_priv; 54 struct dm_i2c_ops *ops; 55 struct udevice *emul, *dev; 56 bool is_read; 57 int ret; 58 59 /* Special test code to return success but with no emulation */ 60 if (msg->addr == SANDBOX_I2C_TEST_ADDR) 61 return 0; 62 63 ret = i2c_get_chip(bus, msg->addr, &dev); 64 if (ret) 65 return ret; 66 67 ret = get_emul(dev, &emul, &ops); 68 if (ret) 69 return ret; 70 71 /* 72 * For testing, don't allow writing above 100KHz for writes and 73 * 400KHz for reads 74 */ 75 is_read = nmsgs > 1; 76 if (i2c->speed_hz > (is_read ? 400000 : 100000)) 77 return -EINVAL; 78 return ops->xfer(emul, msg, nmsgs); 79 } 80 81 static const struct dm_i2c_ops sandbox_i2c_ops = { 82 .xfer = sandbox_i2c_xfer, 83 }; 84 85 static int sandbox_i2c_child_pre_probe(struct udevice *dev) 86 { 87 struct dm_i2c_chip *i2c_chip = dev_get_parentdata(dev); 88 89 /* Ignore our test address */ 90 if (i2c_chip->chip_addr == SANDBOX_I2C_TEST_ADDR) 91 return 0; 92 if (dev->of_offset == -1) 93 return 0; 94 95 return i2c_chip_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, 96 i2c_chip); 97 } 98 99 static const struct udevice_id sandbox_i2c_ids[] = { 100 { .compatible = "sandbox,i2c" }, 101 { } 102 }; 103 104 U_BOOT_DRIVER(i2c_sandbox) = { 105 .name = "i2c_sandbox", 106 .id = UCLASS_I2C, 107 .of_match = sandbox_i2c_ids, 108 .per_child_auto_alloc_size = sizeof(struct dm_i2c_chip), 109 .child_pre_probe = sandbox_i2c_child_pre_probe, 110 .ops = &sandbox_i2c_ops, 111 }; 112